更新本地通知的开火日期并取消之前的通知

Question

我知道这里和那里有一些关于如何删除可能是全部或特定通知的本地通知的问题.我也经历了本地通知类引用并找到了一些方法,如重复时间间隔,开火日期,警报体,时区等...但我无法找到有关如何修改已经设置的开火日期的某种信息.如果用户设置今天的日期和下午4:50的通知,但是如果用户希望修改设定的日期/时间,发生的事情是通知在两种情况下都会触发.就编程伦理而言,这是一个大错!

实际上我想要的是必须取消之前的通知,即必须将日期修改为已编辑的日期,并且应在新日期设置并触发通知.

这是我如何设置通知,示例代码:

- (void)setNotification
{
    //Set notification after confirmation of saved data

    Class cls = NSClassFromString(@"UILocalNotification");
    reminderNotification = [[cls alloc] init];

    if (cls != nil) 
    {        
       NSDateFormatter *dateFormat = [[[NSDateFormatter alloc]init]autorelease];
       [dateFormat setDateFormat:@"YYYY-MM-dd HH:mm:ss"];
       NSDate *notificationDate = [dateFormat dateFromString:textField2.text];
       reminderNotification.fireDate = notificationDate;
       reminderNotification.timeZone = [NSTimeZone defaultTimeZone];
       NSString *reminderText = [NSString stringWithFormat:@"%@ 's %@ on %@",textField.text,textField1.text,strDate];
       reminderNotification.alertBody = reminderText;
       reminderNotification.alertAction = @"View";
       reminderNotification.soundName = @"lazy_afternoon.mp3";
       reminderNotification.applicationIconBadgeNumber = 1;
       NSDictionary *userDict = [NSDictionary dictionaryWithObject:self.textField1.text forKey:kReminder];
       reminderNotification.userInfo = userDict;
       [[UIApplication sharedApplication] scheduleLocalNotification:reminderNotification];
       [reminderNotification release];
    }
}

任何人都可以指导我如何处理这项任务.

在此先感谢所有:)

Answer 1

使用此方法来安排通知,其中notificationID必须是唯一的

 -(void) scheduleNotificationForDate:(NSDate *)date AlertBody:(NSString *)alertBody ActionButtonTitle:(NSString *)actionButtonTitle NotificationID:(NSString *)notificationID{

    UILocalNotification *localNotification = [[UILocalNotification alloc] init];
    localNotification.fireDate = date;
    localNotification.timeZone = [NSTimeZone localTimeZone];
    localNotification.alertBody = alertBody;
    localNotification.alertAction = actionButtonTitle;
    localNotification.soundName = @"yourSound.wav";

    NSDictionary *infoDict = [NSDictionary dictionaryWithObject:notificationID forKey:notificationID];
    localNotification.userInfo = infoDict;

    [[UIApplication sharedApplication] scheduleLocalNotification:localNotification];
}

使用此方法取消具有该通知ID的特定通知

- (void)cancelLocalNotification:(NSString*)notificationID {
    //loop through all scheduled notifications and cancel the one we're looking for
    UILocalNotification *cancelThisNotification = nil;
    BOOL hasNotification = NO;

    for (UILocalNotification *someNotification in [[UIApplication sharedApplication] scheduledLocalNotifications]) {
        if([[someNotification.userInfo objectForKey:notificationID] isEqualToString:notificationID]) {
            cancelThisNotification = someNotification;
            hasNotification = YES;
            break;
        }
    }
    if (hasNotification == YES) {
        NSLog(@"%@ ",cancelThisNotification);
        [[UIApplication sharedApplication] cancelLocalNotification:cancelThisNotification];        
    }
}

参考: UILocalNotification